Spirent Communications, Huawei, and Xilinx have developed a testbed for true 400G Ethernet networks and equipment, a critical step enabling 400G technology.

While 100G transport is becoming common in backbone networking and in connectivity for business services, traffic demands are accelerating. “We’re seeing 100G even in CMTSs,” said Ross Cassan, Spirent’s director of product marketing. “A couple of years ago, homes might average two set-tops each. Now any home might have 20 devices going. There is a lot of demand coming.”

While communications service providers are now making the transition from 10G to 100G technology, standards bodies are working to define the next speed increment, which will be 400G. Network equipment suppliers are doing preliminary work on 400G products in parallel to the activities of standards bodies, and to make sure they’re on the right path, they require a 400G test environment.

“And we have to get ahead of them all so that they have something to build against,” Cassan told CED.

While it is possible to aggregate links – ten at 40G or four at 100G, for example – the ideal is to get a single 400G link, and that is what Spirent, Huawei and Xilinx say they have done.

Cassan explained that the test technology for 400G is as difficult, if not more difficult, than the 400G technology itself. “The trick is that you have to count it,” he said. “You have one-quarter the time to do it. You have to determine if the packets are arriving in order. We can do all of that.”

Spirent, Huawei and Xilinx have been collaborating for more than six months testing of Huawei’s NE5000E core router, which incorporates Xilinx processors, using the Spirent 400G Ethernet Test System. 

The three have verified the tester works for evaluating 400G systems, ISO layers 1 through 3 (PHY, PCS/MAC, network). Spirent said the tester achieved error free performance with different combinations of streams, frame lengths and rates including a single stream running at full line rate.

Testing 400G devices starts with validating the  link’s ability to pass up to line rate traffic, as well as and testing the functionality, performance, scalability and quality of experience (QoE) of the upper-layer engines that deliver services, Spirent said.

Spirent has developed a complete testing solution for early design and development of 400G Ethernet systems, with a one-slot blade form factor compatible with Spirent’s existing chassis and its other Ethernet products. 

Features of the solution include:

  • Sending and receiving Ethernet frames from 64 to 16K bytes in length
  • Generating and analyzing 400G traffic as a single stream running at line rate or as an aggregation of multiple streams
  • Compensating for small clock differences between link partners with parts per million (PPM) adjustment
  • Delivering per-port and per-stream statistics such as latency, frames out of sequence, frame counts and rates, and layer 1 statistics to help debug physical link problems
  • Allowing modification of generated frame contents
  • Capturing received traffic at wire rate